Preparation of sterile tubing sets



vJune 22, 1943. N. M. NEssET ETAL PREPARAT'ON OF STERILE TUBING SETSFiled Aug. 20, 1941 Patented June 22, 1943 PREPARATION OF STERILE TUBINGSETS YNaurlce M. Nesset, Glenview, and Edward J.

Nawoj, Chicago, Ill., asslgnors to Baxter Laboratories, Inc., Glenview,Ill., a corporation of Delaware Application August 20, 1941, Serial No.407,612

6 Claims.

This invention relates to sterile tubing sets. It is particularly usefulin parenteral therapy.

It is the common hospital practice to give bulk parenteral therapy bymeans of recipient sets consisting of necessary glass or metal partsconnected by means of relatively heavy walled rubber tubing.Furthermore, it is the hospital practice to re-use these recipient setsand it is obvious that incident to this practice that the recipient setsbe cleansed after or before each dispensation. This practice introducesa hazard to this therapy, principally by virtue of the fact that it isrelatively diiiicult to clean the rubber tubing. It is also a relativelyexpensive procedure to clean the rubber tubing as compared to cleaningthe glass or metal parts.

An object of this invention is to provide a new means and method forobviating the hazard and labor incident to cleaning the rubber tubing,as above referred to, without increasing the cost. A further object isto provide a sterile tubing, equipped with fittings, which is ready foruse without cleaning, whereby the cost ls considerably reduced. Otherobjects and advantages will appear as the speciiication proceeds.

The invention may be used with a variety of different types ofapparatus. For the purpose of illustration, there is shown in theaccompanying drawing one formV of apparatus with which the invention maybe employed, the single figure setting forth a plan viewv of tubing andttings which may be employed in the practice of the invention.

In the illustration given, III indicates a thinwalled rubber tubingwhich tends to collapse under atmospheric pressure, particularly uponthe removal of a portion of the air within the same. The tubing may beformed not only of rubber, but also of any other suitable material. Byway of illustration, we have foundthat rubber tubing with a wallthickness of eleven-thousandths of an inch (.011") is satisfactory. Itwill be understood, however, that the wall dimensions may vary with theparticular rubber or other material employed.l It is sufiicient for thepurposes of the invention that the wall structure be such as to collapseunder pressure in the neighborhood of atmospheric.

In use, the tubing I is equipped with fittings at one or both ends. Theiittings will vary widely. In the illustration given, the connectorfitting I I is shown secured to one end of the rubber tubing. In view ofthe fact that thin-walled rubber tubing has an extremely low tensilestrength, it is necessary to reinforce the open end by means of a rubberband I2 placed over the rubber tubing 4after the fitting is in place. Toseal the outer end of the iltting II, a resilient cap I3 is employed.

In the illustration given, the opposite end of the tubing III isequipped with a hollow needle member Il, which is likewise secured tothe tubing by means of a rubber band I5. To seal the hollow needle, itis passed into a vial I6 and through a resilient plug I1, closing thevial.

Instead of using the rubber bands I5, it will be understood that theends of the rubber tubing may be reinforced to provide integral meansfor frictionally-engaging and sealing the ends of the ilttings.'

The assembled set, with the ttings open, is then thoroughly rinsed andlled with distilled Water of satisfactory purity or other suitableliquids, such as a physiological solution of sodium chloride, etc. Whenthe set has been lled with a suitable liquid, the set is hermeticallysealed by placing a rubber tip I3 over the open end of the fitting I Iand inserting the' hollow needle through the rubber sealing plug I1 intothe vial, the vial having been previously illled with the same form ofliquid, such as distilled water, saline solution, or other suitableliquid.

It will be understood that a variety of glass or metal fittings'may beattached to the tubing, and for the sealing thereof, the same or equiv.alent means may be employed.

The setv after thus being illled and closed is then heated to sterillzethe same. If desired, the sterilization may be acccomplished by Wrappingthe tubing set within gauze, canvas, or other suitable supportingmaterial, and placing the same within an autoclave. The heat iscarefully controlled to sterilize the tubing while at the same timemaintaining the liquid inside of the tubing in liquid phase. If desired,the tubing may be placed within a sealed container and sterilizedtherein by autoclaving. Y

In use after autoclaving, one end of the set is opened, allowing thefluid to run out and thus collapsing the tubing, after which the usualprocedure of parenteral therapy is followed.

The advantages of autoclaving the tubing completely lled with a suitablesolution, may be stated as follows:

1. It keeps the tubing distended, thereby pre-i venting adherence of thewalls during autoclavmg.

2. It prevents oxidation and discoloration.

3. It enables checking of the set for leaks prior to the administrationor use.

l 4. It permits starting the parenteral :infusion without removingairfrom the set.

5. It enables the use of simple gauze or canvas wrappings, therebyeliminating the cost 0f the container, reducing labor involved inpreparing the set, and providing the maximum economy in packing andstorage space.

While we have described the parts as consisting of rubber, glass, metal,etc., it will be understood that equivalent materials may be employed,and it will be further understood that variations may be made in thesteps and details recited by those skilled in the art without departingfrom the spirit of our invention.

We claim:

l. A method of preparing sterile tubing, comprising filling thin-walledtubing collapsible under atmospheric pressure with a sterile liquid,sealing the ends, supporting the same, and sterilizing with heat.

2. A method of preparing sterile tubing, comprising filling thin-walledtubing collapsible under atmospheric pressure with liquid, sealing theends, wrapping the same within supporting vmaterial, and steriiizingwith heat.

3. A method of preparing a sterile tubing set, comprising filling, withliquid, a thin-walled tubing collapsible under atmospheric pressure andequipped at its ends with fittings, sealing the fittings, andsteriiizing the set with heat while maintaining the liquid in liquidphase.

4. A method of preparing sterile tubing, comprising filling, withliquid, thin-walled tubing collapsible under atmospheric pressure,provided at one end with a connector fitting and at the other end with ahollow needle, sealing the connector fitting, sealing the needle byinserting the samel through the resilient closure of a vial, the vialbeing lled with liquid, and steriiizing the set with heat.

5. A method of preparing sterile tubing, comprising filling, withliquid, thin-walled tubing collapsible under atmospheric pressure, thetubing being equipped at its ends with fittings, means sealing thefittings, supporting the set within wrapping material, and steriiizingwith heat.

6. A method of preparing sterile tubing, comprising filling thin-walledtubing collapsible under atmospheric pressure with liquid, sealing theends of the tubing, introducing the same into a container, sealing thecontainer, and heating the container to sterilize the contents.

NAURICE M. NESSET. EDWARD J. NAWOJ.

